Background of the invention

Abstract

A PV (photovoltaic) junction box comprises a case, a lid covering the case and a plurality of terminals received within the case. The case has a bottom wall and defines a positive input port and a negative output port, and each terminal having a planar main body retained to the main body. The terminals comprise a first terminal, a second terminal, a third terminal and a fourth terminal, and the main bodies of the terminals are different.

What is claimed is: 
     
       1. A PV (photovoltaic) junction box comprising:
 a case having a bottom wall and a plurality of sidewalls located on a peripheral of the bottom wall and defining a receiving cavity cooperatively with the bottom wall, the case defining a positive input port and a negative output port; 
 a lid covering the case; and 
 a plurality terminals, each terminal having a planar main body mounted to the bottom wall of the case, the terminals comprising a first terminal near the positive input port and a second terminal near the negative output port, respectively, the main body of the first terminal having a larger area than that of the main body of the second terminal, wherein the terminals further comprise a third terminal disposed between the first and the second terminals and near the positive input port, the main body of the third terminal is larger than the main body of the first terminal. 
 
     
     
       2. The PV junction box as claimed in  claim 1 , wherein the terminals further comprise a fourth terminal disposed between the third terminal and the second terminal and near the negative output port. 
     
     
       3. The PV junction box as claimed in  claim 2 , wherein the main body of the fourth terminal is smaller than that of the third terminal but larger than the main bodies of the first and the second terminals. 
     
     
       4. The PV junction box as claimed in  claim 2 , wherein a sequence of the terminals based on areas of the main bodies thereof and arrayed from largest to smallest is: the third terminal, the fourth terminal, the first terminal and the second terminal. 
     
     
       5. The PV junction box as claimed in  claim 4 , wherein the lid has a top wall and a plurality of side walls extending downwardly from a peripheral of the top wall, the side walls are formed with a plurality of latching arms to lock with a plurality of latching holes provide on the sidewalls of the case. 
     
     
       6. The PV junction box as claimed in  claim 2 , wherein two banding portions extend forwardly from front edges of the main bodies of the first and the second terminals to retain wires of two cables inserting into the receiving cavity from the positive input port and the negative output port, respectively. 
     
     
       7. The PV junction box as claimed in  claim 2 , wherein the terminal has a bending portion bent upwardly from a rear edge of the main body and a clamper is attached to the bending portion. 
     
     
       8. A PV (photovoltaic) junction box comprising:
 a case having a bottom wall and a plurality of sidewalls extending upwardly from a peripheral of the bottom wall and defining a receiving cavity cooperatively with the bottom wall; and 
 a plurality terminals received in the receiving cavity, each terminal having a main body retained to the bottom wall and a bending portion bent vertically from the main body, the terminals comprising a first terminal, a second terminal and a third terminal disposed between the first and the second terminals, the third terminal being larger than the first and the second terminal, wherein the terminals further comprise a fourth terminal disposed between the third and the second terminals, and the fourth terminal is smaller than the third terminal, wherein the fourth terminal is larger than the first terminal, and the second terminal is the smaller than the first terminal, wherein the main body of the first terminal is larger than the main body of the second terminal but smaller than the main body of the fourth terminal, and the main body of the third terminal is the largest. 
 
     
     
       9. The PV junction box as claimed in  claim 8 , wherein the side walls include a pair of first sidewalls parallel to each other and extending along a front-to-back direction, a pair of second sidewalls parallel to each other and extending along a right-to-left direction and two inclined connecting sidewalls connects one of the second sidewall located in the front of the case and the two first sidewalls, respectively; and the case has a riveting portion vertically and outwardly protruding from the connecting sidewall. 
     
     
       10. The PV junction box as claimed in  claim 8 , wherein the main body of the terminal has a through positioning hole, and the bottom wall of the case is provided with a post inserting into the positioning hole to retain the terminal. 
     
     
       11. The PV junction box as claimed in  claim 8 , further comprising a lid, the lid defines a first hole at a rear end thereof, and the case defines a corresponding second hole outside the receiving cavity, a tying rope passes through the first and the second holes to tie the lid and the case together. 
     
     
       12. A PV junction box comprising:
 a casing defining a long lengthwise direction and a transverse direction with two chamfered structure around two opposite corners on one lengthwise side in the lengthwise direction; 
 a receiving cavity formed in the casing; 
 a positive port and a native port located around the corresponding chamfered structure; and 
 a plurality of terminals commonly arranged in the cavity along the lengthwise direction and including two opposite outer terminals and the remaining inner terminals in the lengthwise direction; 
 a plurality of diodes connecting between every two adjacent two terminals, respectively; 
 said two opposite outer terminals being shorter than the remaining inner terminals in the lengthwise direction; 
 each of said terminals being arranged with expanded and narrowed sections along the transverse direction under condition that every adjacent two terminals are complementarily and alternately arranged with each other in the transverse direction, wherein said casing further defines another lengthwise side extending in the lengthwise direction and arranged opposite to said lengthwise side in the transverse direction, under condition that each of the terminals occupies a substantial portion of the whole dimension of said another lengthwise side in the lengthwise direction while only the inner terminals make contribution to occupy a substantial portion of the dimension of said lengthwise side between the chamfered structure in the lengthwise direction. 
 
     
     
       13. The PV junction box as claimed in  claim 12 , wherein the diodes are arranged offset from one another in both the lengthwise direction and the transverse direction. 
     
     
       14. The PV junction box as claimed in  claim 12 , wherein one of the opposite outer terminals is a positive terminal and the other is a negative terminal under condition that positive terminal is larger than the negative terminal. 
     
     
       15. The PV junction box as claimed in  claim 14 , wherein there are two said inner terminals under condition that one of said two inner terminals closer to the positive terminal is larger than the other of said two inner terminal while both of said two inner terminals are larger than the positive terminal.